CNS
Brain and Spinal Cord
PNS
12 Pairs of Cranial Nerves
31 Pairs of the spinal nerves
Carries sensory afferent messages to the CNS from sensory receptors.
Cerebral Cortex Function
Is the center for humans highest functions governing thought, memory, reasoning, sensation and voluntary movement.
Cerebral Cortex
Is the cerebrum's outer layer of nerve cell bodies which look like "gray matter" because it lacks myelin
Frontal Lobe
Areas Concerned with personality, behavior, emotions, and intellectual function.
PRECENTRAL GYRUS: Initiates voluntary movement.
Parietal Lobe
Postcentral gyrus: Primary center for sensation
Occipital Lobe
Primary visual receptor.
Temporal Lobe
Primary auditory receptor
Wernicke's area
In Temporal lobe
Associated with language comprehension. When damaged, receptive aphasia results meaning the person hears sound, but it has no meaning (Like hearing a foreign language)
Broca's area
In frontal lobe, mediates motor speech.
When injured, expressive aphasia results meaning the person cannot talk. (Can understand language and know what he or she wants to say but can produce it)
Crossed Representation
The left cerebral cortex receives sensory information from and controls motor functions to the right side of the body, while the right cerebral cortex receives sensory information from the left side of the body.
Left Cerebral Cortex
Receives sensory information from and controls motor function to the right side of the body
Right Cerebral Cortex
Receives sensory information from and controls motor function on the left side of the body.
Cranial Nerve I
Olfactory
Function: Smell
Cranial Nerve II
Optic
Function: Vision
Cranial Nerve III
Oculomotor
Function: Motor Function of extraoccular movement, opening of eyelids
Parasympathetic functions of pupil constriction and lens shape.
Cranial Nerve IV
Trochelear
Motor Function: Down and inward movement of the eye
Cranial Nerve V
Trigeminal
Motor Function: Muscles of mastication (chewing)
Sensory Function:sensation of face and scalp, cornea, mucous membranes of mouth and nose
Cranial Nerve VI
Abducens
Motor Function: Lateral movement of the eye
Cranial Nerve VII
Facial
Motor Function: facial muscles, close eye, labial speech, close mouth
Sensory Function: Taste (sweet, salty, sour, bitter) on the anterior 2/3 of the tongue
Parasympathetic function-saliva and tear secretion
Cranial Nerve VIII
Acoustic
Sensory Function: Hearing and equilibrium
Cranial Nerve IX
Glossopharyngeal
Motor Function-pharynx including swallowing and phonation
Sensory Function- taste on posterior one-third of the tongue, pharynx (gag reflex)
Cranial Nerve X
Vagus
Motor Function: Pharynx and Larynx (talking and swallowing)
Sensory Function: General sensation from carotid body, carotid sinus, pharynx , viscera
Parasympathetic function: carotid reflex
Cranial Nerve XI
Spinal
Motor Function: Movement of the trapezius and sternomastoid muscles
Cranial Nerve XII
Hypoglossal
Motor Function: Movement of the tongue
Cerebellar System
Complex motor system coordinates movement, maintains equilibrium and helps maintain posture and maintains muscle tone.
Cerebellar System Location
Coiled structure under the occipital lobe.
Receives information about what kind of motor messages are being sent from the cortex to the muscles.
Testing persons gait/balance
Observe persons gait as they walk 10 to 20 feet, turns and returns to the starting point
Normal Finding:The person moves with a sense of freedom; The gait is smooth, rhythmic and effortless, the opposing arm swing is coordinated and the turns are smooth.
Balance Test Abnormal Findings
Stiff, immobile posture. Staggering or reeling. Wide base of support.
Lack of arm swing or rigid arms.
Unequal rhythm of steps
Slapping of foot.
Scraping of toe of shoe.
Ataxia
Uncoordinated or unsteady gait
Tandem walking
Assess balance by asking person to walk a straight line in a heel-to-toe fashion.
This decreases the base of support and will accentuate any problem with coordination.
Normal Finding: The person can walk straight and stay balanced.
Romberg Test
Ask the person to stand up with feet together and arms at the sides.
Once in a stable position, wait 20 seconds.
Normal Finding: a person can maintain posture and balance even with visual orienting information blocked, although slight swaying may occur.
Positive Romberg Sign
Loss of balance that occurs when closing the eyes.
Occurs with cerebellar ataxia (multiple sclerosis, alcohol intoxication) loss of proprioception and vestibular function
Knee Bend/Hop in Place
Demonstrates normal position sense, muscle strength and cerebellar function.
Rapid Alternating Movements
Assess coordination by asking person to pat the knees with both hands, lift up, turn hands over and pat knees with the backs of the hands. Then ask them to do it faster.
Normal Finding: Done with a equal turning and quick rhythmic pace
Finger to finger test
With person's eyes open, ask that he or she use the index finger to touch your finger, then his or her own nose.
After a few times move your finger to a different spot.
Normal Finding: Persons movement smooth and accurate
Finger to nose test
Ask the person to close their eyes and to stretch out the arms.
Then ask person to touch the tip of their nose with each index finger, alternating hands and increasing speed.
Spinothalmic tract
Has sensory fibers that transmit the sensations of pain, temperature, and light touch
1=Hypoesthesia
2=Anesthesia
3=Hyperesthesia
1=decreased touch sensation
2=absent touch sensation
3=increased touch sensation
Peripheral Neuropathy
Abnormal Finding for Vibration Test
Is worse at the feet and gradually improves as you move up the leg.
Loss of vibration sense
Occurs with peripheral neuropathy like
Diabetes, and alcoholism
*Often first sensation lost
Posterior Column Tract
Conducts the sensations of position.
Proprioception
Without looking you know where your body parts are in relation to space and each other, vibration and finely localized touch.
Stereognosis
Test the persons ability to recognize objects by feeling their forms, sizes and weights.
Example: With person's eyes closed place a familiar object like a paper clip, key, coin, cottonball or pencil in their hands and ask them to identify it.
Normal Findi
Kinesthesia
Test the persons ability to perceive passive movements of the extremities. (Positions) Move a finger on the big toe up and won and ask the person to tell you which way it moved.
Make sure the persons's eyes are closed and that they understand the test.
Graphesthesia
Is the ability to "read" a number by having it traced on the skin. With the person's eyes closed, use a blunt instrument to trace a single digit number or a letter on the palm.
Ask the person to tell you what it is.
This is a Good measure of sensory loss
Deep tendon reflex
Reveals the intactness of the reflex arc at specific spinal levels as well as the normal override on the reflex of the higher cortical levels.
Consists of: Biceps, Triceps, Brachioradialis, Quadriceps, Achilles Reflexes
Testing the Deep tendon reflex
The limb should be relaxed and the muscle partially stretched. Stimulate the reflex by directing a short, snappy blow of the hammer onto the muscles insertion tendon.
Example: Knee Jerk or Patellar Area
Visceral Reflex
Example: Pupillary response to light and accommodation
Plantar Reflex
Position the thigh in a slight external rotation.
With the reflex hammer, draw a light stroke up the lateral side of the sole of the food AND inward across the ball of the foot like in an upside down J shape.
Normal Response: Plantar flexion of the toes (
Babinskis sign
Pathologic Reflex
Abnormal response is dorsiflexion of the big toge and fanning of all toes.
"Upgoing toes"
Occurs with upper motor neuron disease of the corticospinal tract.
4+ Reflex
Hyperreflexia with clonus
3+ Reflex
Exaggerated Response
2+ Reflex
Normal Response
1+Reflex
Weak Response
Slow Conduction
Occurs with aging
Decreases between 5 and 10% with aging
This delay at the synapse causes the impulse to take longer to travel resulting in diminished touch and pain sensation and sense of smell.
Decrease in cerebral blood flow
Occurs with aging
Can cause dizziness and loss of balance with position change. These people need to be taught to get up slowly to prevent falls.
During an assessment of the cranial nerves, the nurse finds the following; lack of blinking in the right eye with corneal reflex, intact ability to sense light touch on face, loss of movement with facial features on the right side. This would indicate dys
Motor component of VII
When the nurse is testing the triceps reflex, what is the expected response?
Extension of the arm
During the assessment of deep tendon reflexes, the nurse finds that a patients responses are normal bilaterally. Indicate what number is used to indicate normal deep tendon reflexes when documenting this finding?
2+ Reflex
Myelin
The white insulation on the axon that increases the conduction velocity of nerve impulses
Abdominal Reflex
Normal response is the ipsilateral contraction of the abdominal muscles with an observed deviation of the umbilicus towards the stroke.
reflex arc
(1) receptor: site of stimulus action (2) sensory neuron: transmits afferent impulses to CNS (3) integration center: synapse (4) motor neuron: conducts efferent impulses from the integration center to an effector organ (5) effector: muscle fiber/gland cel
objective vertigo
feels like the room is spinning
subjective vertigo
____ is present when the patient experiences the sensation of turning or moving around in space. Objective vertigo is the sensation of objects moving around the patient.
glasgow coma scale
15 = no coma, 7 coma, 3 profound coma. Eye opening, verbal response, motor response
nystagmus
back-and-forth oscillation of the eyes; occurs with disease of the vestibular system, cerebellum, or brainstem
Aphasia
the loss of the ability to speak, write, and/or comprehend the written or spoken word; usually caused by damage to left hemisphere
coma
state of profound unconsciousness from which person cannot be aroused
decerebrate rigidity
Upper extremities- stiffly extended, adducted, internal rotation,palms pronated. Lower extremities-stiffly extended, plantar flexion; teeth clenched;hyperextended back;indicates lesion in the brain stem at midbrain or upper pons
decorticate rigidity
Decorticate rigidity occurs when there are lesions of the cerebral hemispheres. Damage to the brain occurs above the brainstem and cerebellum (i.e., above the tentorium). There is upper extremity flexion (arms in fetal position) and lower extremity extens
dysphasia
impairment in speech consisting of lack of coordination and inability to arrange words in their proper order
Paralysis
Loss of motor function due to a lesion in the neurologic or muscular system or loss of sensory innervation
Paresthesia
abnormal sensation (such as burning, prickling, or tingling sensation, often in the extremities; may be caused by nerve damage or peripheral neuropathy
Tic
repetitive twitching of a muscle at inappropriate times
deep tendon reflex
Reveals the intactness of the reflex arc at specific spinal levels as well as the normal override on the reflex of the higher cortical levels.
Consists of: Patella, Biceps, Triceps, Brachioradialis, Quadriceps, Achilles Reflexes
Superficial Reflexes
- initiated by gentle cutaneous stimulation
Ex) plantar reflex is initiated by stimulating the lateral aspect of the sole of the foot
- response is downward flexion of toes
- indirectly test for proper corticospinal tract functioning
- Babinski's sign: ab